I really like WordPress, and I really like JetPack. I use the plugin on many client websites, who usually have their own WordPress.com  account, which is necessary to enable the plugin successfully.
Most of them however choose not to sign up for a payment plan, which as of 2017 leads to (now rather annoyingly frequent) JetPack upsell messages at the top of the admin screen. So I as the administrator, am constantly exposed to such messages, and I was wondering how to suppress them – not being the target audience here.
Thanks to a super helpful article by Matt Medeiros I found a great solution with this one-liner of code he as kindly supplied on his website, together with his opinion on such messages:
/* remove JetPack upsell messages */ /* https://mattreport.com/disable-jetpack-upsell-ads/ */ add_filter( 'jetpack_just_in_time_msgs', '_return_false' );
Add this to your child theme’s functions.php file and those admin nags are history!
Thanks Matt!